LAKE SEBU, South Cotabato (MindaNews/20 October)—An awful smell of dead, rotten fish has blanketed this town’s premier tourist attraction this past week after a fish kill hit Lake Sebu once again that killed at least 20 tons of cultured tilapia, as affected fish cage operators did not immediately conduct a clean-up.
The fish kill–the worst this year–was blamed on what locals call “kamahong,” a phenomenon known to happen even before the fish cages invaded the lake in the late 1980s, usually during wet season.
In January 2012, around 50 tons of tilapias were also lost to kamahong, which is usually characterized by the sudden rise of the water’s temperature.
“In the last five days, the smell of rotten fish flesh was terrible,” Jessie Ralya, a lakeside resident of Purok Lot 70, told MindaNews on Sunday outside his hut from where majority of the fish cages devastated by the fish kill was just a stone’s throw away.
An estimated 100 kilograms of dead tilapias still remained floating Sunday in the fish cages, leaving behind a foul smell that, according to him, “is already tolerable.”
Ralya said the remaining floating dead fishes “were what was left of the cleaning operation overnight Saturday by workers of the fish cage operator who buried the bulk of them beside the lake.”
The latest fish kill to hit Lake Sebu, from which this town got its name, was monitored starting as early as October 6, when the water sampling conducted by the Bureau of Fisheries and Aquatic Resources (BFAR) in parts of the lake on dissolved oxygen level reached two micrograms per liter (µg/L), said Rudy Muyco, the lake warden.
For fishes to survive in the lake, the normal level should be 5 µg/L or above but on October 12, dissolved oxygen level was below 1(µg/L), he added.
“There were gradual fish kills during the period. It became severe on October 13 with the fishes floating up dead,” Muyco told MindaNews, recalling that prior to the severe incident, it has been raining for days due to typhoon Santi and then suddenly a strong sunlight.
“There was an abrupt change in water temperature [from cold to warm] that resulted to the massive fish kill,” he added.
The fish kill has affected an estimated 15 hectares of fish cages, though in varying degrees as some suffered total losses while others just five percent, Muyco said.
Lilia Paloma, 66, lamented that it was the second year in a row for them to be hit by the fish kill, wondering aloud “what’s happening to the Philippines.”
“We have the war in Zamboanga, followed by the magnitude 7.2 earthquake in Bohol and now a fish kill in Lake Sebu,” she told MindaNews as she and her husband Warlito,69, were about to go to their fish cages to catch “ayungin” (silver perch) so they could sell them to the market to buy rice or coffee.
“Just like last year, we are victims of the fish kill. We’ve lost our tilapias that were about to be harvested. We don’t know where to get financing to start anew,” she said.
For the fish kill last year, the couple said they have not received any assistance that was extended by the BFAR, like fingerlings.
The couple maintains 10 fish cages of tilapia, which can be harvested after nine or 10 months.
“I’m not anymore thinking about our losses, it is just giving me a headache and breaks my heart,” Warlito told MindaNews.
Muyco, the lake warden, confirmed that BFAR had extended assistance last year to the victims of the fish kill, but did not have an answer when presented with the case of the Paloma couple.
For the victims of the recent fish kill, Muyco said the local government unit and other concerned government agencies will still be meeting to discuss the assistance that would be provided to those affected.
Beyond the lake’s carrying capacity
Muyco blamed the fish kill on the changing climate condition and acts of man, the latter, he stressed, contributing much to the degradation of Lake Sebu, one of this town’s three lakes.
The other lakes are Seloton and Lahit.
Last March, Dr. James Namocatcat, a marine biologist at the Mindanao State University in General Santos City, had proposed a moratorium on fish cage farming for Lake Sebu because it is carrying beyond its capacity.
At the time, the scientist found out that in some parts of the lake, even at a depth of four feet, dissolved oxygen nearly reached zero level.
That is especially true where the fish cage operations are located, he added, but cautioned that there’s still a need to conduct a deeper scientific investigation “before reaching a conclusive finding.”
Namocatcat explained that it is not only the caged tilapia stocks that need dissolved oxygen to survive in the lake; water hyacinths, algae and bacteria living there also consume them.
He said the weather is also a key factor that leads to oxygen depletion at the lake, particularly if there is no sunlight for days as it would deprive the photosynthesis process that allows aquatic plants and algae to produce oxygen.
“An interplay of factors actually caused the degradation of the lake,” Namocatcat told MindaNews then.
He also cited the residential owners who flush their wastes directly to the lake.
To save Lake Sebu from dying, Namocatcat suggests that a moratorium on fish cage operations be declared to allow the lake to regenerate. Once it recovers, he said, the number of fish cages must be regulated in accordance with the lake’s carrying or assimilation capacity.
With a moratorium, the impact on fish cage operators would be temporary, he said, adding that if this is not done, the effects of a dead lake would be long-term.
Apparently, the call for moratorium fell on deaf ears.
Also in a report in February 2012 following the fish kill then, a BFAR study recommended the dismantling of excess fish cages by the LGU in order to maintain the lake’s carrying capacity.
Leonisa Alfaro, South Cotabato Protected Area Superintendent (PASu) for the Allah Valley Protected Landscape, placed the lake’s carrying capacity at around 320 fish cages.
But with 4,586 fish pens based on the record of the lake warden’s office, the lake is carrying 13 times beyond its capacity.
“The condition of Lake Sebu is critical in terms of fish culture. The level of dissolved oxygen, which is most probably the most critical water quality variable in the lake, is lethal to aquaculture species (tilapia) based on the series of water quality trials conducted,” the BFAR study then showed.
The study found out that the causes of the February 2012 fish kill were overstocking of fishes, overfeeding and domestic run-off/chemical wastes, resulting to oxygen depletion, toxic gases and pollutants.
The Municipal Agriculture Office had placed the area occupied by the fish pens at 56 hectares or 15 percent of the lake’s 354 hectares.
Republic Act 8550 or the Fisheries Code of 1998, however, provides that aquaculture must utilize only 10 percent of the lake’s total area.
Muyco, the lake warden, said a massive rehabilitation, including the dismantling of excess fish cages, for Lake Sebu “maybe seen soon” with the completion of the Lake Sebu Management Plan or “Ligtas Lawa” masterplan, which was recently submitted to the South Cotabato provincial government.
Reached through a series of focus group discussions, the plan recommended a 10-point approach to save Lake Sebu from dying.
“A strong political will is indispensible,” the plan’s number one recommendation said.
“Limit the number of fish cages to sustainable level. This could be balanced between the calculated carrying capacity and the 10 percent total surface water area as provided by law,” the plan also recommended.
Jojit Tupas, the administrator of the Lake Sebu local government unit (LGU), said the mayor’s office has yet to get hold of the plan, stressing the LGU is concerned about the state of the town’s biggest lake and major tourism attraction.
“There’s a need indeed to amend the local ordinance as it may be too obsolete already,” he told MindaNews, noting the amendment may take form from the master plan.
Need for consultation
For Ferdinand Tapel, another fish cage operator, regulating the fish pens on the lake “poses no problem.”
“As long as there is proper consultation so the voices of the people can be heard,” the 41-year old father of three told MindaNews.
Tapel, who operates eight fish cages, suggested that the LGU should give priority to the “tumandok” or the local inhabitants than the outsiders in the utilization of the lake for fish cage farming. (Bong S. Sarmiento/MindaNews)